After user equipment (UE) sends uplink data to an evolved NodeB (eNB), the eNB usually needs to send feedback information to the UE.
In Long Term Evolution (LTE), if UE sends uplink data to an eNB by using an uplink shared resource A on a physical uplink shared channel (PUSCH), where the uplink shared resource A further includes a demodulation reference signal (DM-RS) corresponding to the UE, the eNB receives and decodes the uplink data according to the DM-RS corresponding to the UE. After correctly receiving and decoding the uplink data, the eNB sends acknowledgement information (ACK) to the UE or sends negative acknowledgement information (NACK) to the UE by using an agreed downlink resource B on a physical HARQ indicator channel (PHICH). It can be learnt from an LTE communications protocol that a resource location of the agreed downlink resource is obtained by means of calculation according to a resource location of the uplink shared resource A and the DM-RS.
During a process of implementing the present disclosure, the prior art has the following disadvantages: When multiple UEs use a contention based uplink data transmission mode, an eNB may allocate a same uplink shared resource and DM-RS to the multiple UEs. When the multiple UEs send uplink data to the eNB by using the same uplink shared resource, a conflict occurs because the different UEs use the same uplink shared resource and the same DM-RS. Consequently, the eNB cannot correctly send feedback information to the different UEs according to an agreed downlink resource.